Density functional theory 106 density functional theory 30 Density-functional-theory 25 Technology: general issues 23 Research & information: general 22 Electronic structure 21 Computation theory 19 Probability density function 19 Calculations 15 Chemistry 14 Energy gap 13 History of engineering and technology 11 First principles 10 Density-functional theory calculations 9 Transition metals 9 Electronic.structure 8 Molecular dynamics 8 Research and information: general 8 Graphene 7 Optical properties 7 chemistry 7 Adsorption 6 Article 6 Biology, life sciences 6 Carbon 6 Charge transfer 6 Liquids 6 Molecules 6 article 6 Chemical bonds 5